A government witness testified Friday that two cotton balls and a syringe needle — allegedly saved after a steroids injection — tested positive for Clemens’ DNA.

“Mr. Clemens is the likely source of that biology,” said Alan Keel of Forensic Science Associates.

Earlier in the trial, Brian McNamee, Clemens’ former strength and conditioning coach, said he had injected Clemens with steroids in 1998, 2000 and 2001 and with human growth hormone in 2000.

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